Geese fly in V-formations. At the apex is a leader. Without a leader, geese would become a disorderly gaggle. This analogy applies to the international order. After World War I, no international leader emerged. America became isolationist. Britain and France were bled white by the war. Germany lay in ruins with her future prospects crippled by excessive reparations. Revolution consumed Russia as Lenin’s Bolsheviks sought to consolidate power and control. After the unconditional surrenders of Germany and Japan ended World War II in 1945, a leader did emerge: the United States. Roosevelt, Marshall, Truman and members of Congress learned the tragic lessons of two decades of global retrenchment and were determined to establish and maintain a more stable and peaceful international order. Germany and Japan would be rehabilitated by the Marshall Plan and the rest of Europe rebuilt. Bretton Woods would create a sound international financial system. The UN would become an international forum. As Soviet Russia digested the states of Eastern Europe and the Cold War hardened, the NATO alliance would be created to prevent further aggression. Ideology turned this complicated conflict into a more simplistic division between the “Free World” and monolithic, godless communism. And the U.S. sought as allies any country that opposed communism irrespective of the degree of its authoritarian rule. Throughout the Cold War and since, however, the common denominator to maintaining the international order was the U.S. and as some would argue, its role as “the indispensable global power.” Despite this hyperbole and more than a few catastrophic strategic blunders such as the Vietnam and second Iraq wars, global stability and security remained a function of engaged American leadership. Mostly it was for good. Still, eighteen years of conflict have elapsed for America since September 11th, 2001. The Middle East and Gulf are less secure and remain in greater turmoil since the U.S. intervention into Afghanistan and then into Iraq. Ironically, both Barack Obama and Donald Trump ran for president promising to end the wars in Afghanistan and Iraq. While American military presence has been greatly reduced, conflicts have spread to Syria, Yemen and parts of Africa. Following the 2016 election, Trump’s America First policies began reducing Washington’s global leadership initially by rejecting multilateralism. Ironically, both Barack Obama and Donald Trump ran for president promising to end the wars in Afghanistan and Iraq. While American military presence has been greatly reduced, conflicts have spread to Syria, Yemen and parts of Africa Under Trump, America withdrew from the Trans Pacific Partnership (TPP) and the Paris Climate Change Accord. The president called NATO obsolete and threatened further American retraction from Europe. The Joint Comprehensive Plan of Action (JCPOA) with Iran was abrogated. Leaving the International Nuclear Forces Treaty (INF) followed. And extending the New START strategic arms treaty is in doubt. The administration promised trade wars with neighbors to the north and south and imposed large tariffs on Chinese goods. This latest tariff war could lead to a global recession or worse. And the UN was downgraded in the process. The consequence is the decline and retrenchment of American international leadership. Compounding this contraction has been Trump’s inexplicable embrace of authoritarian rulers in China, Russia and North Korea. Further, Trump’s active support for BREXIT and Britain’s new Prime Minister Boris Johnson confirms the antipathy towards multilateral organizations such as the EU. In politics as in nature, vacuums are abhorred. Presidents Xi and Putin along with Dear Leader Kim and Israeli Prime Minister Benjamin Netanyahu are moving to fill the global vacuums created by this administration. China’s “Belt and Road” and Russian “active measures” are clear indicators of Beijing and Moscow assuming more prominent international leadership roles. Emmanuel Macron has attempted to assume in part the role of a democratic global leader. But France is hardly a superpower. And Europe’s influence is in decline given growing internal political divisions resulting in weak governments throughout much of that continent. BREXIT reinforces these trends. Indeed, the infamous “wall” Trump hopes to build and have Mexico fund across the 1200 mile southern border is a metaphor for how America First is reversing seven decades of U.S. internationalism and leadership. The critical questions are how the absence of American leadership will alter the international order and whether these directions will be reversible after Trump’s first or possible second term. The prospects seem ominous. The weakening of the central pillar of the international order has been largely under reported and unrecognized. No Democratic candidates especially Joe Biden who understands these dangers, has touched on foreign policy and the dangers caused by the malign consequences of absent U.S. global leadership. Health care, the environment, education, the economy and presidential conduct dominant political debate. Yet, the willful decline of U.S. global leadership may be the most damaging issue of all. But who is listening? Dr. Harlan Ullman is a Senior Advisor at the Atlantic Council. His latest book is Anatomy of Failure: Why America Has Lost Every War It Starts. The writer can be reached on Twitter @harlankullman